dazaar

hypermarket

Share hypercores on a one to one basis like a marketplace

npm install hypermarket

Usage

First setup a seller

const hypercore = require('hypercore')
const pump = require('pump')
const market = require('./market')

const m = market('./tmp')

const feed = hypercore('./tmp/data')

feed.append('valuable')

const seller = m.sell(feed, {
  validate (remoteKey, cb) {
    console.log('this key wants our hypercore', remoteKey)
    cb(null)
  }
})

seller.on('ready', function () {
  console.log('seller key pair fully loaded ...')

  const buyer = m.buy(seller.key)

  buyer.on('feed', function () {
    console.log('got the feed!')
    buyer.feed.get(0, function (err, data) {
      console.log('first feed entry: ' + data)
    })
  })

  buyer.on('validate', function () {
    console.log('remote validated us')
  })

  const stream = seller.replicate()
  
  pump(stream, buyer.replicate(), stream, function (err) {
    console.log('replication ended', err)
  })
})

API

const market = hypermarket(storage)

Create a new hypermarket instance

const seller = market.sell(feed, options)

Sell a hypercore by creating a new seller.

Options include:

{
  validate (remoteKey, cb) // wheather a remote key can get a copy of this feed,
  validateInterval: 1000 // how often to validate
}

seller.buyers(cb)

Get a list of all the buyers of this feed

seller.on('ready')

Emitted when the seller is fully ready and has loaded it's keypair

seller.discoveryKey

A hash of the sellers public key that can be used for discovery purposes.

seller.key

The public key of this seller. Needed to buy the data.

const buyer = market.buy(sellerKey)

Buy a hypercore by creating a buyer instance. It is expected that the remote seller can verify that you purchased the data through a third party some how

buyer.on('ready')

Emitted when the buyer is fully ready and has fully loaded it's keypair.

buyer.key

The buyer public key. All buyers have the same public key through out the market instance. This is the remote key the seller sees in the validate function

buyer.seller

The seller public key.

buyer.discoveryKey

A hash of the seller public key that can be used to discover the seller on a network.

buyer.on('feed', feed)

Emitted when we have a feed. If we previously succesfully validated this is triggered right away. Otherwise it is triggerd after the first remote validation.

buyer.on('validate')

Emitted first time a remote seller validates us.

buyer.on('invalidate', err)

Emitted when a remote seller invalidates us with the error they provided.

buyer.feed

The feed we bought.

bool = market.isSeller(instance)

Helper to determine if an instance is a seller.

bool = market.isBuyer(instance)

Helper to determine if an instance is a buyer.

Swarm

A network swarm based on hyperswarm is included as hypermarket/swarm

const swarm = require('hypermarket/swarm')

swarm(buyer) // swarms the buyer
swarm(seller) // swarms the seller

License

MIT